Seven months pregnant covers weeks 25 through 28, putting you right at four weeks in length for that month. This places you at the tail end of the second trimester, with the third trimester officially starting at week 28. If the math feels confusing, you’re not alone. Pregnancy is counted from the first day of your last menstrual period, which means it actually spans 40 weeks, or closer to 10 calendar months rather than the nine most people expect.
Why Pregnancy Months Don’t Match Calendar Months
A calendar month averages about 4.3 weeks, but pregnancy months are typically grouped into neat four-week blocks. That mismatch is why converting between weeks and months never feels straightforward. The full 40-week timeline adds up to 280 days, which is just over nine calendar months. Some sources round to nine months, others say ten. Neither is wrong; they’re just using different math.
The week count is what your provider actually tracks, because it’s far more precise. If someone asks how far along you are, “28 weeks” tells a doctor or midwife exactly where you stand. “Seven months” is a useful shorthand for everyone else.
What’s Happening With Your Baby
At the start of month seven, around week 25, your baby is roughly the size of a head of cauliflower. By week 28, they measure about 37.6 centimeters (nearly 15 inches) from head to heel. Growth during this stretch is rapid, with fat stores building under the skin to help regulate body temperature after birth.
The lungs are a major focus of development right now. Specialized cells in the airways begin producing surfactant, a slippery substance that keeps the tiny air sacs from collapsing. This process starts around week 24, but month seven is when it really ramps up. Surfactant production is one of the key reasons every additional week in the womb matters for babies born early. The eyes also begin opening and closing during this period, and your baby can respond to bright light filtered through your abdomen.
Brain development accelerates too. The surface of the brain, previously smooth, starts forming the grooves and folds that allow for more complex processing. Your baby is practicing breathing movements, swallowing amniotic fluid, and cycling between sleep and wake periods you can often feel.
Physical Changes You Can Expect
Month seven is when pregnancy starts to feel physically demanding. Your uterus is large enough to press on your diaphragm, which can leave you short of breath, especially when lying on your back. That same pressure pushes down on your bladder, so frequent bathroom trips become the norm. Leaking a little urine when you laugh, sneeze, or cough is common and nothing to worry about.
You may notice Braxton Hicks contractions for the first time. These are mild, irregular tightenings of your abdomen that tend to show up in the afternoon or evening, often after physical activity. They’re not labor contractions. They come and go without a pattern and don’t increase in intensity the way real contractions do.
Back pain is one of the most common complaints during this stretch. Pregnancy hormones loosen the connective tissue in your pelvis to prepare for delivery, and the weight of your growing uterus pulls your center of gravity forward. Together, those changes put strain on your lower back. Heartburn and constipation also pick up because those same hormones slow digestion, while the uterus crowds your intestines. Some people develop varicose veins in their legs or hemorrhoids as blood volume increases and circulation slows in the lower body.
Screenings Around Month Seven
If you haven’t already had your glucose screening for gestational diabetes, it’s likely coming up now. The standard testing window falls between weeks 24 and 28. The test involves drinking a sugary solution and having your blood drawn afterward to see how your body processes the sugar. If results come back elevated, a longer follow-up test confirms whether gestational diabetes is present.
Your prenatal visits may also shift to every two weeks around this time, up from the monthly schedule you’ve been on. Your provider will be checking your blood pressure, measuring your belly, and tracking the baby’s position and heart rate more closely as you move into the third trimester.
The Third Trimester Transition
Week 28 marks the official start of the third trimester, so reaching seven months pregnant means you’re crossing that threshold. From here, you have roughly 12 weeks until your due date at 40 weeks. Prenatal appointments become more frequent, fetal movement counts become more important, and your body shifts into preparation mode for labor and delivery. The finish line is closer than it feels.